Regular Expressions 101

Pro

1st Alternative^(?!(\d)\1{2}-(\d)\1{1}-(\d)\1{3})$

^start of line

Negative Lookahead(?!(\d)\1{2}-(\d)\1{1}-(\d)\1{3})

Group 1(\d)

\da digit

\1{2}the text saved by group 1, repeated exactly 2 times

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 2(\d)

\da digit

\1{1}the text saved by group 1, repeated exactly 1 time

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 3(\d)

\da digit

\1{3}the text saved by group 1, repeated exactly 3 times

$end of line

2nd Alternative^(?!(\d)\1{8})$

^start of line

Negative Lookahead(?!(\d)\1{8})

Group 4(\d)

\da digit

\1{8}the text saved by group 1, repeated exactly 8 times

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

^(?!(\d)\1{2}-(\d)\1{1}-(\d)\1{3})$|^(?!(\d)\1{8})$

New

888888888
123456789
888-88-8888
123-45-6789
111-22-3333
333-33-3333

888888888
123456789
888-88-8888
123-45-6789
111-22-3333
333-33-3333